KRAS and non-small cell lung carcinoma: Recently, emerging biomarkers, including genetic alterations of the Kirsten rat sarcoma viral oncogene homolog (KRAS), the human epidermal growth factor receptor 2 (HER2), the mesenchymal-epithelial transition (MET) and rearrangements of the neurotrophic tyrosine receptor kinase (NTRK) and the rearranged during transfection (RET) genes, have gained significant attention because of the development of selective inhibitors, some of which have already received approval for clinical use in pretreated NSCLC patients [3,4].